/Engine/Source/Runtime/MeshDescription/Public/MeshAttributeArray.h
Get an attribute value for the given element ID. Note: it is generally preferable to get aTMeshAttributesRefand access elements through that, if you wish to access more than one.
template<typename T> T GetAttribute ( const ElementIDType ElementID, const [FName](API\Runtime\Core\UObject\FName) AttributeName, const int32 AttributeChannel ) const